Circuits, antennas, and other electrical elements are important components of consumer electronics. Currently, these electrical components are constructed on various types of substrates using, for example, laser direct structuring (LDS) and pad printing. LDS uses a laser beam to etch a pattern such as a circuit or antenna pattern into a thermoplastic material that is doped with an organic metal additive. A microscopically rough track is formed where the laser beam hits the doped thermoplastic material. The etched thermoplastic material is then subjected to a copper bath followed by metal plating. LDS is very time consuming and costly.
In pad printing, a pattern is etched into a plate that is subsequently filled with electrically conductive material. A pad is then placed onto the plate with enough pressure to transfer electrically conductive material to the pad. Finally, the pad is pressed onto a substrate transferring the electrically conductive material to the substrate in the shape of the etched pattern. This process is repeated several times to transfer a sufficient amount of electrically conductive material onto the substrate.
Thermal transferring techniques also have been used to make electrically conductive materials. However, these methods require multiple steps, long dwell times, high temperatures, and high pressures to transfer electrically conductive material. In addition, these methods commonly use environmentally undesirable materials such as halogenated organic compounds.
It is therefore desirable to provide a fast, consistent, cost-effective, and/or environmentally friendly method for transferring electrically conductive materials to substrates, and particularly, substrates used with wireless communication devices.